Method and apparatus for applying labels to containers



A ril 28, 1970 s. 1.. BELCHER ET L. 3,503,993

METHOD AND APPARATUS FOR APPLYING LABELS TO CONTAINERS Filed July 18.1966 2 Sheets-Sheet 1 52 7k x i) 52 [HZ/622160215 22 50 514M054. L. Each52 5y JZZeo/VE R. GAOTAMQN April 28, 1970 s. L. BELCHER ETA'L 3,508,993

METHOD AND APPARATUS FOR APPLYING LABELS TO CONTAINERS Filed July 18,1966 2 Sheets-Sheet 2 INVENTORS' \STQMUEL L5LCHE BY 5 z) I 4 7f? UnitedStates Patent 3,508,993 METHOD AND APPARATUS FOR APPLYING LABELS TOCONTAINERS Samuel L. Belcher and Jerome R. Grothjan, Toledo,

Ohio, assignors to Owens-Illinois, Inc., a corporation of Ohio FiledJuly 18, 1966, Ser. No. 565,797 Int. Cl. B65c 3/08 U.S. Cl. 156-215 9Claims ABSTRACT OF THE DISCLOSURE The method of applying plastic labelsto containers wherein a turntable with adjacent sectors provided with avacuum and an electrostatic charge is used to pick up labels from astack, transfer the charge to the container surface and apply the labelto the charged surface while simultaneously relieving the vacuum tofacilitate the label application. Thereafter the label is bonded to thecontainer surface.

This invention relates generally to methods and apparatus for applyinglabels to containers, and more particularly to the application of filmsto containers by electrically charging a container and transferring afilm thereto to be held by electrostatic attraction until it ispermanently bonded in place.

In the manufacture of certain plastic and glass containers, plasticlabels have been applied to the containers while they are being formed.It has been found that if a plastic label is applied to a containerduring the formation of the container, a relatively thick label isrequired. It has also been observed that the application of the labeltakes a significant portion of the overall time expended during themanufacture of the containers.

It is now proposed in accordance with the present invention to applyextremely thin plastic labels or other plastic films to containers afterthey have been fully manufactured by a process wherein the film isapplied to the container and is temporarily held there by electrostaticattraction until it is permanently bonded in place. In general, themethod includes steps of applying an electric charge to the surface ofthe containers, placing the film in contact with the charged surface ofthe container to transfer the film to the container and hold the film onthe container by electrostatic attraction, and subsequently permanentlybonding the film onto the container. In a preferred embodiment, thetransferring of the film to the container is carried out by picking up afilm with a vacuum head to retain the film on the head by a pressuredifferential, positioning the vacuum head at the charged surface of thecontainer to place the film in contact with the charged surface, andincreasing pressure within the vacuum head to release the film andthereby transfer it to the charged surface. The final bonding step maybe accomplished by applying heat to the film by thermal conduction or byapplying ultrasonic energy to the film, or by shrinking the film on tothe container.

The preferred apparatus for carrying out the method of the inventionincludes a rotary turn-table which has sections for picking up pieces offilm by vacuum, and in alternation with the vacuum pick-up sections hascharging sections for transferring electric charge to a container. Filmsare supplied to the turn-table from a stack of films which contacts thecircumference of the turn-table, and the vacuum pick-up sections simplytake the top film off of the stack when they come into contact with thatfilm. Containers are transported to a place adjacent to the rotaryturn-table, and the transporting means includes a rotatable support onwhich a container rotates as a film is being applied to it from theturn-table so as to wrap 3,508,993 Patented Apr. 28, 1970 the filmaround the container. The container is first electrically charged by acharging section of the turntable, and then a film is transferred fromthe next vacuum pick-up section to the container. While the film is heldin place by electrostatic attraction, the container is transported to abonding station where the film is permanently bonded in place by one ofseveral available bonding methods, i.e., by thermal conduction or byultrasonic energy or by shrinking the film onto the container.

Accordingly, it is an object of the present invention to provide animproved method and apparatus for ap plying plastic labels or otherplastic films to containers by a combination of vacuum handling andelectrostatic attraction that is eflicient, expeditious and economical.

Another object of the invention is to provide an efiicient way ofelectrically charging containers and of applying plastic films to thecharged containers where they are held in place by electrostaticattraction.

A further object of the invention is to provide a method and apparatusfor picking up plastic films from a stack with a vacuum head andtransferring the films to containers which have been electricallycharged.

Another object of the invention is to provide apparatus for alternatelycharging a container and transferring a film to the container at alabeling station so that the container may be transported rapidly alonga line leading to and from the labeling station.

Other objects of this invention will appear in the following descriptionand appended claims, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

ON THE DRAWINGS FIGURE 1 is a schematic plan view of a preferredapparatus embodiment of the invention;

FIGURE 2 is a schematic fragmentary view of a label carrying andcharging turn-table included in the embodiment of FIGURE 1;

FIGURE 3 is a fragmentary perspective view of the label carrying andcharging turn-table together with a plenum;

FIGURE 4 is a top view of the plenum; and

FIGURE 5 is a top view of a vacuum pick-up head.

Before explaining the present invention in detail, it is to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of being practiced or carried out in various ways. Also,it is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.

AS SHOWN ON THE DRAWINGS A conveyor 10 or other suitable containertransport means is provided to transport containers 12 along a straightpath leading to a turn-table 14. The containers 12 may be made of glassor plastic, and at this stage of the processing they have already beenformed into their final shape.

When a container 12 reaches the turn-table 14, it enters a scallopedportion 16 of the turn-table and is carried on a rotary support of theturn-table. The turn-table 14 rotates in a counterclockwise directionthrough and then remains at a labeling station 20 for a predeterminedperiod of time while a label is applied to the container 12. Anythermoplastic type of material conventionally used for labels oncontainers may be employed, e.g., the materials disclosed in the Patent3,235,433. After a label has been applied, the turn-table 14 rotatesanother 90 to bring the container 12 to a position where it istransferred to another in-line conveyor 34 which carries the containerswith labels on them to a bonding station 40. The containers are gatedinto the bonding station by means of stops 38. At the bonding station40, the label or other plastic film which has been applied to eachcontainer is permanently secured to the container by any one of severalavailable bonding processes. Specifically, the bonding process may becarried out by heat sealing, by ultrasonic bonding, or by shrinking thelabel onto the container. It is not essential to seal the entire surfaceof the label to the container, it being sufficient to seal only theedges of the label to the container.

Referring again to the turn-table 14, when a container 12 is in theposition midway between the two conveyors 10 and 34, it is next toanother turn-table 28 which rotates about a post 26. The turn-table 28is divided into six equal sectors. Three of these sectors 30 serve aselectrical charging heads and are spaced at angles of 120 from eachother. The other three sectors 32 serve as vacuum pick-up heads, andthey are likewise spaced 120 from each other but are located in betweenthe charging sectors 30. The charging heads 30 are electricallyinsulated from each other and from the pick-up heads 32 as by electricalinsulation at 31. The turn-table 28 is rotated in a counterclockwisedirection so that the charging sectors 30 and the pick-up sectors 32alternately come into contact with the container 12 at the labelingstation 20. As any single sector moves past and in contact with thecontainer 12 at labeling station 20, the container rotates through onecomplete revolution in a clockwise direction. Thus, when charge is beingapplied to the container from one of the charging sectors 30', theentire circumference of the container becomes charged due to its contactwith one of the charging sectors 30. Similarly, when the container 12 atstation 20' is in contact with a plastic film on one of the vacuum heads32, the container rotates through a full revolution so that the plasticfilm is wrapped completely around the container as indi cated in thedrawings.

A label 24 is shown as it is being picked up from a stack of labels byone of the vacuum heads 32 of the turn-table 28. The label 24 is one ofa stack 22 of labels which is urged by a spring and head 42 into contactwith the vacuum head 32. The turn-table 28 may momentarily be stationarywhen a head 32 is centered with a label 24 of stack 22. The vacuum inthe vacuum pick-up sectors 32 is provided by a suction apparatus whichis operatively connected to the pick-up sectors so as to produce avacuum therein when a given pick-up sector is centered with and incontact with a label of the stack 22.

The suction apparatus may be constructed as shown in FIGURES 3, 4 and 5.In FIGURE 3, two sectors 30 and 32 are shown mounted for rotation on acircular stationary plenum 46 which is divided into two halves 51 and 53by a partition 47. Plenum half 53 is at atmospheric pressure or higher,but vacuum is applied to plenum half 51 by a pump (not shown). Plenumhalf 51 has a semicircular slot 48 through its top wall via which vacuumis applied to the pick-up heads 32. Each of the latter heads 32 ishollow and has an opening 50 through its bottom wall which registerswith the plenum Opening 48 as the head rotates from the label stack 22to the container 12 at station 20. Thus, vacuum is transferred fromplenum 46 through openings 48 and 50 to the pick-up head 32 so long asOpening 50 is in registry with semicircular opening 48. The pickup head32 may have additional small openings 52 through its vertical face forapplying vacuum to a label from the stack 22 to hold the label on thepick-up head. When the pick-up head reaches station 20', the opening 50moves out of registry with the slot 48 and into registry with slot 49,so the vacuum in head 32 is released to allow transfer of the label tothe container at station 20. An electric charge is applied to a chargingsector 30 after that sector has passed the stack of labels 22 and justbefore it contacts the container 12 at station 20. The chargingapparatus is electrically connected to the charging sectors 30, so as toapply charge thereto as a given sector rotates from the stack 22 to thelabeling station 20. The charging apparatus 60 may be a power supply orbattery having one of its terminals connected to a contact 62 which isadapted to apply charge to the charging sectors 30 but not to the vacuumpick-up sectors 32. For this purpose, each charging sector may be madeof metal and may have a metal flange 64 projecting upward from its topedge as shown in FIGURE 3. The contact 62 engages the metal flange 64 ashead 30 moves past it but does not engage any part of the vacuum pick-upheads 32.

As the turn-table or head assembly 28 rotates counterclockwise incontact with a container 12, electric charge is transferred from itssector 30 to the surface of container 12 as the container 12 at station20 rotates on its rotatable support. After the electric charge has beenaplied to the container 12, the vacuum pick-up sector 32 adjacent thecharging sector 30 is rotated into contact with the container 12 atlabeling station 20'. The container 12 is then rotated through anothercomplete revolution as the surface of vacuum pick-up sector 32 passes bythe container, and in this manner a label 24 is rolled onto thecontainer 12. As the label is being applied, pressure within the vacuumpick-up sector contacting container 12 is increased to release the labelfrom the pick-up sector. The pressure is increased at least to the pointwhere no vacuum exists and may be increased to provide a positivepressure which aids in transferring the label 24 to the container.

After the label has been applied to a container at the labeling station20, the label is held in place by electrostatic attraction of thecharged surface of the container for the label. This attraction holdsthe label in place temporarily until the label may be more permanentlybonded to the container. Thus, while the container is being transportedfrom the labeling station 20 to the conveyor 34 and via the conveyor 34to the bonding station 40, the charge on the container continues to holdthe label in place. At the bonding station 40, the label is afiixed tothe container by heat sealing, or by application of ultrasonic energy,or by shrinking the label onto the container, as previously mentioned.

The invention provides a method of applying plastic labels or otherplastic films to containers by a combination of vacuum transfer andcharge transfer steps which results in the labels being temporarily heldin place by electrostatic attraction until they can be permanentlybonded to the container. The invention includes a method and apparatusfor picking up plastic films from a stack with a vacuum head andtransferring the films to containers which have been electricallycharged. The charging is accomplished before the label is applied to thecontainer by means of transferring the charge from a charging head whichmoves past the container in alternating sequence with the vacuum pick-uphead. Thus, the labels are applied in a most eflicient manner.

We claim:

1. A method of applying a plastic film to a container comprising thesteps of applying an electric charge to the surface of the container,applying a vacuum to a vacuum pick-up head for removing a film from astack, placing said pick-up head and said film in contact with eachother to retain said film on said head by a pressure differential,positioning said head at said charged surface of said container to placesaid film in contact with said charged surface, increasing pressurewithin said head to release said film therefrom and transfer said filmto said charged surface by electrostatic attraction, and permanentlybonding said film to said container.

2. A method of applying a plastic film to a container comprising thesteps of electrically charging a surface of a charging head, applying avacuum to a vacuum pick-up head for removing a film from a stack,placing said pickup head and said film in contact with each other toretain said film on said head by a pressure differential, contactingsaid container with said charging head to transfer a charge from saidcharging head to said container, contacting said charged container withthe film on said pick-up head, increasing pressure within said pick-uphead to release said film from said pick-up head and transfer said filmto said charged surface of said container where said film is held inplace by electrostatic attraction, and permanently bonding said film tosaid container.

3. In an apparatus for applying a plastic film to a container, thecombination of rotary means mounted for rotation having sections forpicking up pieces of film by vacuum and having between and alternatingwith said vacuum pick-up sections charging sections for transferringelectric charge to a container, means for supplying pieces of film tosaid rotary means to be picked up on said vacuum pick-up sections.transporting means for supplying containers to a place adjacent saidrotary means, said transporting means including a rotatable support forproviding rotation of a container thereon at said place and in contactwith said rotary means so that a container is rotated on said supportwhile in contact wtih a charging section and is further rotated while incontact with a vacuum pick-up section of said rotary means to transfer apiece of film to said container, and a bonding station in the path ofsaid transporting means where said film piece is permanently bonded tosaid container.

4. The apparatus of claim 3 in which said rotary means comprises aturn-table having vacuum pick-up sections and charging sections inalternation about the circumference thereof.

5. The apparatus of claim 4 in which said rotatable support is a part ofa second turn-table by which said containers are brought into contactwith said first named turn-table.

6. The apparatus of claim 5 in which said containers are fed to saidsecond turn-table by an in line conveyor and are fed by another in lineconveyor from said second turn-table to said bonding station.

7. In an apparatus for applying a plastic film to a container, thecombination of a turn-table mounted for rotation about an axis thereof,said turn-table comprising a plurality of hollow vacuum pick-up sectionsand a plurality of charging sections located between and alternatingwith said vacuum pick-up sections, means for supplying pieces of film tosaid turn-table to be picked up on said vacuum pick-up sections, each ofsaid vacuum pick-up sections having an apertured face for contacting andreceiving a film piece to carry the same thereon, means for applyingvacuum to the interior of said vacuum pick-up sections including aplenum having an opening therein to communicate with the interior ofeach vacuum pick-up section, each said pick-up section having an openingtherein to register with said opening in said plenum during a portion ofone revolution of said turntable, transporting means for supplyingcontainers to a labeling station adjacent said turn-table, means forapplying an electrical charge to said charging stations at apredetermined position thereof between said film supplying means andsaid labeling station, and a bonding station in the path of saidtransporting means.

8. A method of applying plastic labels to containers, comprising thesteps of applying a vacuum to one sector of a turntable for picking uplabels from a stack, applying an electrostatic charge to an adjacentsector of the turntable, moving the sector with the vacuum, relative tothe stack of labels so as to pick up a label, moving the container andthe turntable relative to each other so that the electrostatic charge onthe charged sector is transferred to the container surface, again movingthe container and the turntable relative to each other so that the labelis attracted onto the charged container surface from the sector with thelabel and thereafter permanently bonding the label onto the containersurface.

9. The method as described in claim 8, including the further step ofrelieving the vacuum so as to facilitate the transfer of the label tothe charged container surface.

References Cited UNITED STATES PATENTS PHILIP DIER, Primary Examiner US.Cl. X.R.

